This application claims the priority of German patent application Serial No. 198 55 747.7 filed Dec. 3, 1998. The disclosure of the above-referenced German patent application, as well as that of each U.S. and foreign patent and patent application mentioned in the specification of the present application, is incorporated herein by reference.
The present invention relates to improvements in apparatus for manipulating elongated rod-shaped articles, and more particularly to improvements in apparatus for monitoring certain characteristics of rod-shaped articles by means of a pneumatic testing fluid. Still more particularly, the invention relates to improvements in substantially sleeve-like sealing devices which are utilized in such types of apparatus to establish fluid-conveying connections between the articles and the monitoring means during transport of articles past or through a testing station. The invention also relates to combinations of sealing devices with fluid-conveying parts in the above outlined apparatus.
Typical examples of rod-shaped articles or products which can be tested in the apparatus of the present invention are plain or filter cigarettes, cigars, cigarillos or other rod-shaped smokers"" products as well as sections of filter rods for tobacco smoke.
It is customary to test successive rod-shaped smokers"" products (hereinafter called cigarettes for short with the understanding that such term is to embrace all kinds of rod-shaped smokers"" products which can be tested with a gaseous fluid medium) by resorting to a conveyor which transports the cigarettes toward, past and beyond a testing station. The end portions of the cigarettes are received in resilient (elastic) sleeves which couple them to fluid-admitting or fluid-receiving components of the testing apparatus. The testing operation can include a detection of the presence or absence of holes in the tubular wrappers of cigarettes, the quality of customary perforations which are provided in the wrappers to admit streamlets of cool atmospheric air into the column of tobacco smoke flowing into the mouth of the smoker of a lighted cigarette, the resistance which the so-called filler of a cigarette offers to the flow of a gaseous fluid and/or others. As a rule, or in many instances, compressed gaseous testing fluid is admitted into one end portion of a cigarette moving sideways through the testing satiny, and the characteristics of testing fluid issuing at the other end of the cigarette are examined for the purpose of ascertaining the quality of the tested product.
It is often sufficient to utilize for each cigarette on the testing conveyor a single resilient sleeve, e.g., a sleeve which ensures that compressed air supplied by a compressor or the like cannot escape into the atmospheres on its way into one end portion of a cigarette advancing toward the testing station. The sleeves are carried by the testing conveyor and are movable axially toward and away from sealing engagement with the adjacent end portions of the cigarettes which are about to be tested. The sleeves have round sockets for reception of end portions forming part of customary round (cylindrical) cigarettes, and oval sockets for reception of the end portions of so-called oval cigarettes (i.e., cigarettes having elliptical or substantially elliptical cross-sectional outlines). Reference may be had to U.S. Pat. No. 3,948,084 which fully describes several presently known and utilized testing conveyors for rod-shaped smokers"" products.
A drawback of presently known testing apparatus which are utilized to ascertain certain characteristics of oval cigarettes is that the angular and/or axial positions of their resilient sealing sleeves do not invariably correspond to optimum angular and/or axial positions for predictable and damage-free introduction and/or extraction of end portions of oval cigarettes. It if often necessary to replace defective elastic sleeves with fresh sleeves, and each such operation can result in improper mounting of one or more sleeves. This contributes to the number of rejects. The likelihood of improper mounting of sleeves for the end portions of oval or like non-circular cylindrical cigarettes is less pronounced during assembly of a testing apparatus in the plant which turns out such apparatus; however, the likelihood of improper mounting (such as misalignment) of sleeves is much more pronounced in the cigarette making plant where the sleeves must be replaced at frequent intervals. The danger of improper mounting of fresh sleeves in a cigarette making plant is especially pronounced if such tasks are entrusted to unskilled or to freshly hired persons.
An object of the invention is to provide a novel and improved apparatus for pneumatically testing cigarettes and analogous rod-shaped products of the tobacco processing industry.
Another object of the invention is to provide novel and improved sealing devices for use in the testing apparatus.
A further object of the invention is to provide novel and improved combinations of sealing devices and carriers therefor which can be utilized in the above outlined testing apparatus.
An additional object of the invention is to provide a novel and improved testing conveyor which can be put to use in the above outlined apparatus to transport rod-shaped products of the tobacco processing industry toward, through and beyond a testing station where the products are tested with currents of a gaseous testing medium, such as air.
Still another object of the invention is to provide sleeve-like sealing devices for the end portions of oval cigarettes which are configurated in such a way that they can be properly mounted on tubular carriers only and alone if they assume optimum positions relative to their carriers in a testing conveyor.
A further object of the invention is to provide sealing devices which can be rapidly and predictably mounted in a testing apparatus even by unskilled persons.
Another object of the invention is to provide sealing devices for the end portions of oval cigarettes which are less likely to deform, deface and/or otherwise damage the end portions of cigarettes than heretofore known sealing devices.
One feature of the invention resides in the provision of a sealing sleeve for non-circular end portions of rod-shaped articles of the tobacco processing industry which advance with elongated tubular carriers on a rotary conveyor past a pneumatic testing station. The sleeve comprises an at least partially resilient body having at least one annular portion surrounding and form-lockingly engaging at least one tubular section of a carrier to thus maintain the sleeve in a predetermined position relative to the conveyor and relative to an end portion of an article being tested. If the articles are so-called oval cigarettes, cigars, cigarillos, filter mouthpieces or the like (i.e., if such articles have at least substantially elliptical cross-sectional outlines), the at least one annular portion of the sleeve can have an at least substantially oval outline.
The arrangement can be such that the at least one annular portion of the sealing sleeve has an internal profile which is complementary to an external profile of the respective carrier in at least one of the directions including circumferentially and longitudinally of the carrier. One of the profiles can include at least one protuberance (such protuberance can extend at least substantially radially of the carrier), and the other profile can include a complementary recess (e.g., a radially extending bore or hole) for the at least one protuberance.
The body of the sealing sleeve can have a second annular portion which is adjacent the at least one annular portion and is arranged to enter a complementary annular recess of the respective carrier to thus releasably hold the sealing sleeve and the carrier against movement relative to each other in the longitudinal direction of the carrier. The sleeve can be slipped off the carrier in response to requisite deformation of its at least partially resilient body.
Another feature of the present invention resides in the provision of a pneumatic testing apparatus for plain or filter cigarettes, cigars, cigarillos or filter mouthpieces for tobacco smoke having non-circular cross-sectional outlines. The testing apparatus comprises a conveyor (e.g., a drum having axially parallel peripheral flutes for the rod-shaped smokers"" products to be tested) which is rotatable about a predetermined axis, a tubular carrier which is rotatable with the conveyor, and an at least partially resilient sealing sleeve having a socket (such as a recess in an end face of the sleeve) arranged to receive an end portion of a product to be tested and an internal profile surrounding and complementary to an external profile of the carrier to releasably hold the sleeve against movement in at least one of the directions including (a) axially of the conveyor and (b) circumferentially of the carrier.
The sleeve and/or the carrier can have an at least substantially oval cross-sectional outline.
The aforementioned profiles can be configurated to establish between the sleeve and the carrier a form-locking connection; such connection permits separation of the sleeve from the carrier and/or application or reapplication of the sleeve over the carrier in response to adequate deformation of the at least partially resilient sleeve.
One of the profiles can have at least one protuberance, and the other profile then exhibits a complementary recess for such protuberance.
It is also advisable to configurate the carrier and the sleeve in such a way that one of the profiles exhibits a ring-shaped projection and the other profile has a complementary annular groove for the ring-shaped projection to thus hold the sealing sleeve and the carrier against movement relative to each other in the axial direction of the conveyor; such axial movement is possible only in response to sufficient deformation of the sleeve.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved sealing sleeve itself, however, both as to its construction and the mode of using the same in a testing apparatus, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawings.